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International
Standard
ISO 11427
Third edition
Jewellery and precious
2024-04
metals — Determination of
silver — Potentiometry using
potassium bromide
Joaillerie, bijouterie et métaux précieux — Dosage de l’argent —
Méthode potentiométrique utilisant le bromure de potassium
Reference number
© ISO 2024
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Published in Switzerland
ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 1
6 Apparatus . 2
7 Sampling . 2
8 Procedure . 2
8.1 Determination of potassium bromide solution factor .2
8.1.1 General .2
8.1.2 Preparation of silver standards .2
8.1.3 Titration of the standard silver solution .2
8.1.4 Calculation of the potassium bromide standard solution factor .3
8.2 Determination .3
8.2.1 Preparation of the sample solution .3
8.2.2 Elimination of palladium .3
8.2.3 Titration of the sample solution .3
9 Calculation and expression of results . 3
9.1 Calculation .3
9.2 Repeatability .4
10 Test report . 4
Bibliography . 5
iii
Foreword
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The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
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rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
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This document was prepared by Technical Committee ISO/TC 174, Jewellery and precious metals, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 410,
Consumer confidence and nomenclature in the diamond industry, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 11427:2014) which has been technically
revised.
The main changes are as follows:
— deletion of “in silver alloys” in the title;
— change of the scope by extending it to alloys containing from 100 to 999 parts per thousand;
— addition of oxygen content for r
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